El gat és petit.

El is the masculine singular definite article in Catalan, equivalent to the.

It agrees with gat, which is a masculine singular noun here.

Some basic article forms are:

• el = masculine singular
• la = feminine singular
• els = masculine plural
• les = feminine plural

So el gat means the cat.

Often, yes: gat is the masculine form, and gata is the feminine form.

However, in some contexts, the masculine form can also be used more generally, especially when the cat’s sex is unknown or not important.

So:

• el gat = the male cat / the cat
• la gata = the female cat

És is the 3rd person singular present tense of the verb ser (to be).

So it means is.

The full pattern is:

• jo sóc = I am
• tu ets = you are
• ell/ella és = he/she is

In El gat és petit, és matches el gat, which is singular.

Because Catalan usually does not need a subject pronoun when the subject is already clear.

In English, you say It is small.
In Catalan, if the subject is already named, you simply say:

• El gat és petit

You do not need an extra pronoun like it.

Catalan is a language that often drops subject pronouns, because the verb form already gives useful information.

In Catalan, adjectives often come after the noun.

So:

• el gat petit = the small cat
• El gat és petit = the cat is small

That is very normal word order.

You can sometimes put adjectives before the noun, but that often adds a stylistic or emphatic effect, and it is not the most basic pattern learners should start with.

Yes. Catalan adjectives usually agree in gender and number with the noun they describe.

Forms of petit:

• petit = masculine singular
• petita = feminine singular
• petits = masculine plural
• petites = feminine plural

Examples:

• El gat és petit.
• La gata és petita.
• Els gats són petits.
• Les gates són petites.

The accent in és helps show the correct written form and distinguishes it from es, which is a different word.

• és = is
• es = a reflexive/clitic pronoun, as in verbs like es diu

So the accent matters.

It also marks the stressed vowel in the word.

In standard Catalan, és is pronounced roughly like ess.

A few notes:

• the s is pronounced
• it is a short, clear word
• it is not pronounced like English ays

So El gat és petit has a clear ess sound in the middle.

Catalan, like Spanish, has two main verbs meaning to be: ser and estar.

Here, ser is used because petit describes a characteristic of the cat: its size.

So:

• és petit = is small

That is the normal choice.

Very broadly:

• ser = identity, characteristics, what something is like
• estar = state, condition, location, how something is at a given moment

For a basic description like this, ser is the right verb.

Not if you want the same full sentence.

El petit gat means the small cat.
That is a noun phrase, not a complete sentence.

El gat és petit is a full sentence because it contains a verb: és.

So:

• El petit gat = the small cat
• El gat és petit = the cat is small

You would change the article, noun, verb, and adjective so they all agree:

• Els gats són petits.

Changes:

• el → els
• gat → gats
• és → són
• petit → petits

Catalan agreement is very important, so all those pieces must match.

Usually not in this sentence.

If you are talking about a specific cat, Catalan normally uses the article:

• El gat és petit.

A bare singular count noun like gat by itself would usually not sound right here.

So for a basic sentence about the cat, keep el.